Gravitational Waves from Extreme Mass Ratio Inspirals
Tuesday 16 May 2017
to 14:30 at
Peter Diener (Louisiana State University)
Extreme Mass Ratio Inspirals (EMRIs) are expected to be one of the most important sources of gravitational wave signals for LISA, a proposed gravitational wave detector mission for ESA. An EMRI is an astrophysical system consisting of a super massive black hole (as found in the center of most galaxies) with an orbiting stellar mass compact object (such as a black hole or neutron star). Observations of gravitational waves from such systems will enable us to perform very strict tests of general relativity as well as provide detailed information about the evolution of super-massive black holes. However, this is only possible if we can compute the gravitational waveforms predicted by general relativity with sufficient accuracy.
I will discuss the conceptual and computational challenges involved in modeling such systems. This includes a description of the concept of self-force; a force arising from the particle interacting with its own field (including general relativistic effects). Point particle approximations of the small object are often used resulting in the need for decomposing the field produced by the particle into a singular and a regular piece. I will describe the traditional mode sum regularization approach and contrast it with a new approach using an "effective source" and outline the path towards calculations of EMRI gravitational waveforms.
(Host: S. Rosswog)